Resinous products from aldehydes and acrylic amides



Patented Sept. 12, 1939 I I nrzsmous PRODUCTS FROM mamas I AND'AORYLlCAMIDES I Daniel E. strain, Wilmington. 15.1.. minor to E. I. du Pont dcNcmoun & Comm! Wilmington, Del., a corp ration No Drawing. ApplicationJuly 8, 1938i 1 Serial No. 89,657

30 Claims. (01. 260-42) This invention relates to a process for theproduce resins having a great variety of useful preparation of syntheticresins and more particphysical'and chemical characteristics dependentularly to a process for the preparation of resins upon the kind or amideand aldehyde reacted by the interaction of aldehydes with the amides aswell as upon the presence or absence of water 5 of acids of the acrylicacid series having the genor an alcohol. 5 eral formula Generally thereaction is conducted by heating o an amide, such, for example, asmethacrylamide with an aqueous formaldehyde containing solui n, asuitable catalyst, such for example, as

potassium carbonate being present. To prepare 10 wherein R is hydrogen,a hydrocarbon radical, or a resin a ing il difl'erent properties the nsubstituted hydrocarbon radical. m r amide. such. ior example, asmethacryli; i known th t t polymerizable esters of amide is'reacted withformaldehyde in the presunsaturated organic acids, such, for example, ase ce of a mono r alcohol and a suitab e acid methyl acrylate, methylmethacrylate, and highcatalyst- W ndu t n the eact on in the 1 er estersof these unsaturated organic acids can presen e of an alcohol, t isusually p e l to be polymerized to give resins having highly us have inaddition to the alkaline material a, cataful characteristics. Because oftheir unusual lys of a aci a u e present such s phthalic physical andchemical properties a great many a hydride; I

important uses have been found for them, but he Prod c isolated trom theinteraction of 20 their field of use could be considerably extended analdehyde with an amide of a po m by providing a series or resins fromsubstantially organic acid in he presence or absence of water the samesource which have higher melting or an alcohol isin the monomeric formand has points, greater resistance to abrasion, and differrtain definitesolubility acter s cs. These cut solubility characteristics.characteristics can be readily changed y 2 An object of the presentinvention is to pro--, v t ns'th m nomeric prod t to the polymeric videsynthetic resins, by the interaction of the form. This conversion. canbe accomplished genamides of unsaturated organic acids with aldeorally yemp yi Well know?! P ly e hydes, having many of the above enumerated de-Processes fll d ca al 511011, f r pl as sirable characteristics. Anotherobject of the inheat, ultra-violet light, organic peroxides and the 30vention is to provide a process for the reaction k ut I have found thatthe monomer is susof acrylamide and amides of alpha-substituted n b e tospecial treatment which is fu ly deacrylic acids with the loweraldehydes, and th r scribed below. by produce a reaction product whichcan be sub- 1 shall now illustrate by way of examples sev- 86 sequentlypolymerized to a resinous body. A fureral methods of conducting myinvention, but it ther object of the invention is to provide a processwill be distinctly understood that the invention for reacting an amideof the aforementioned type W ll n e limi ed to e e t ls therein with analdehyde in the presence of water or a oundvolatile, liquid, organichydroxy compound in Ercample 1.-18.5 parts of methacrylamide 40 whichthe hydroxy groupis attached to aliphatic monomer were mixed with 20.25parts of 37% 40 carbon atoms. A still further object of theinformaldehyde solution and 1.13 parts of potasvention is thepreparation of clear, water-resistl m arbonate- The solution was warmedto ant resins which can be applied or laid down about 5!) or 60 C. andallowed 'to stand for sevfrom water solutions and used as stifiening andoral hours. At this time 2.8 parts of 80% lactic crease-proofing agentsfor textiles and asabackacid were added and-the mixture thoroughly ingfor pile fabrics. Yet another object of the stirred. 0n standin for ourd y he r action invention is to provide new compositions of matmixtureset to a clear, colorless, hard, and tough ter. Other objects andadvantages of the invenresin which could be sawed, turned, and othertionwill hereinafter appear. wise worked to shaped articles. When used as Ihave fo nd that highly useful resins can be a size or as a backing forpile fabrics, it was ap- 50 prepared by reacting the monomeric and polyplied immediately after acidification. The fabric meric amides ofpolymerizable unsaturated orwas allowed to stand at room temperature.Durganic acids with'the lower aldehydes. This Ten ing the course ofseveral days the resin hardened action may if desired be conducted inthe presin place.

B5 ence of water ora lower aliphatic alcohol, to Example 1I.-One mol ofmeth'acrylamide 56 monomer was warmed with one mol of formaldehyde (40%in water) and 3& mol of barium hydroxide. After all the methacrylamidehad passed into solution 5% tartaric acid, based on the methylolderivative, was added. The solution containing about 62.5% of themethylol derivative was then filtered and used-to impregnate gel rayon.The product was centrifuged and dried at 90 C. and then heated for 20minutes at 150C. The product had an angle of crease of 112 compared with84 for the control which was not impregnated. The angle of crease whichis a measure of crease resistance was determined by winding the threadaround a double edged blade while supporting a weight of 40 grams. Itwas creased in this position for 30 minutes, then unwound and cut intosections each of which formed one angle. These angles were measured witha protractor and the values given above represented averages of themeasurements of ten such angles. I

' Example IIL-An aqueous solution of the polymerized methacrylamide waswarmed with an excess of formaldehyde in the presence e: hydrochloricacid. n cooling a resinous product precipitated. and was separated byfiltration, washed with alcohol, and dried. On molding at 140 C. using2000 pounds per square inch pressure, hard, rigid, somewhat opaquearticles were formed.

- Example IV.-A transparent, shaped article molded from polymerizedmethacrylamide was soaked three hours in an'acidined formalin solution(37% aqueous formaldehyde). The polymer swelled but did not dissolve inthe formaldehyde solution and on drying regained its original shape andappearance. The surface of the article was no longer soluble in water.This treatment may be applied to cast polymer. as well as moldedpolymer.

Example V.Sheets of paper prepared from a well beaten, good grade ofbleached sulflte pulp were surface sized with a 2% aqueous solution ofthe polymerized methacrylamide, partly dried, then treated with aaqueous solution of formaldehyde, and dried by passing them over aheated cylinder. These sheets had considerably better-wet strength thanuntreated sheets, their water resistance was equal to that ofrosin-sized sheets, andthey were fairly resistant to penetration bymineral 011.

Example VI.-A mixture of 15 grams mol) of para-formaldehyde, 200 gramsof normal butanol, and 1. cc. of 5% sodium hydroxide solution was heatedwith stirring until a clear solution was obtained. Forty one and onehalf grams of monomeric methacrylamide, Y gram of phthalic anhydride,and 40 grams of benzene were added and the entire mixture was heatedwith stirring for 5 hours at such a temperature that the water-organicsolvent binary mixture distilled oil as fast as it was formed, withsubsequent return of the organic solvent to the reaction mixture. Duringthisperiod 5 cc. of water distilled oil and approximately 4 grams ofprecipitate was formed in the reaction mixture: The product was cooled,filtered, and the solvent removed by distillation in vacuo. The residuewas a viscous, water soluble liquid weighing 54 grams. Upon adding 0.5gram of benzoyl merized to a hard, opaque solid substance which wasinsoluble in acetone, butanol, dioxan, toluene, carbon tetrachloride,water, and caustic soda.

It was somewhat soluble in cold ethylene glycol in which R designates ahydrogen, alkyl, aryl, or aralkyl group, such as methyl, ethyl, phenyl,or phenylethyl. In lieu of formalin or aqueous formaldehyde solutionspara-formaldehyde or trioxymethylene as well as the higher aldehydes,such, for example,,as acetaldehyde, propionaldehyde, butyraldehyde,isobutyraldehyde and other higher aldehydes may be employed. If desiredpart of the aldehyde and/or alcohol may be replaced by an acetal. Thus,for example, if acrylamide is to be reacted with formaldehyde andmethanol, the formaldehyde and methanol may be replaced in part bymethylal.

Products of widely varying properties may be obtained byinterpolymerizing mixtures of monomeric amide-aldehyde condensationproducts with each other or with other polymerizable organic compoundssuch as acrylic and methacrylic acids, their esters and nitriles, vinylcompounds, e. g., organic vinyl esters, vinyl halides, styrene, methylvinyl ketone, maleic acid and its esters, butadiene,2-chlorobutadiene-1,3, etc.

In the processes as disclosed in Examples 1 to 5 inclusive, it has beenfound advisable to form the initial reaction products by the use of analkaline catalyst, such as potassium carbonate, sodium carbonate,potassium hydroxide, sodium hydroxide, or barium hydroxide. In place ofthese alkali metal catalysts any soluble inorganic base or basic salt,or certain organic basic compounds may be used. The reaction ofaldehydes with amides of the type disclosed herein may be carried out inneutral or acidic solution to obtain products of varying properties.

when reacting the amide and aldehyde in the presence of an alcohol, suchfor example, as the monohydric primary, secondary, and tertiary alcoholsin which the alcohols contain preferably less than 5 carbon atoms, such,for example, as methanol, ethanol, normal and isopropanol, normal andisobutanol, the higher aliphatic alcohols, etc., it seems generallyadvisable that the condensation be effected in an acidic medium, such,for example, as the phthalic anhydride of Example 6. In place of thephthalic anhydride, however, other organic acids or their anhydrides orcertain weak inorganic acids and acid salts may be used. Examples of thelatter type of catalyst include phosphoric acid and sodium dihydrog enphosphate.-

When conducting the reaction in the presence of an aliphatic alcohol thecaustic soda is used more to facilitate solution of thepara-formaldehyde in the alcohol employed than as a catalyst and thephthalic anhydride or other type catalyst above referred to is used inquantities preferably more than are suflicient to combine with any freecaustic present.

acids of the acrylic acid series having the general The productresulting from the interaction of the amide with the aldehyde in thepresence of water can be readily polymerized as indicated in theexamples, and it has been generally found that hard, clear, resins maybe prepared by conducting the polymerization of these products in thepresence of water soluble aliphatic carboxylic acids generally, and moreparticularly such acids as lactic acid, tartaric acid, acetic acid, etc.

The resin whetherobtained via the p as covered by Examples 1 to 5 or theprocess of Example 6 may be modified by adding softeners to the solutionbefore polymerization or byadding other known resin forming ingredients,as,v for example, dimethylol urea, phenol-formaldehyde,aniline-formaldehyde, or ketone-formaldehyde condensation products andother monoand polyamides and their methylol derivatives.

The ratio between the amide and aldehyde may be varied over a rangeconsiderably beyond that disclosed by the examples but it has been foundgenerally that products having highly useful physical and chemicalproperties result by eflecting the reaction in accord with theproportions used throughout the examples.

These resins have been found particularly useful when formed in situ asbacking for pile fabrics, as sizing agents for fabrics, as coatings forwood and paper, and as crease-proofing agents for textiles.

From a consideration of the above specification it will be appreciatedthat many changes may be made in the details of the process hereindisclosed without departing from the ,scope of the invention.

I claim:

l. A process of reacting amides of acids of the acrylic acid serieshaving the general formula aC=O-COOH wherein R is a radical of the groupconsisting of hydrogen and a hydrocarbon radical, with lower molecularweight aliphatic aldehydes and thereby producing a condensation product.

2. A process of reacting monomeric amides of the acrylic acid serieshaving the general formula have the general formula wherein R. is aradical of the group consisting of hydrogen and a hydrocarbon radical,with lower molecular weight aliphatic aldehydes and thereby producing acondensation product.

4. -A process of reacting amides of acids, of 'the acrylic series havingthe general formula me d-c 0 on wherein R is a radical of the groupconsisting of hydrogen and a hydrocarbon radical, with formaldehyde andthereby producing acondensation product.

5. A process of reacting monomeric amides of formula mow-coon wherein Ris a radical of the group consisting of hydrogen and ahydrocarbonradical, with formaldehyde and thereby producing acondensation wherein R is a radical oithe group consisting of hydrogenand a hydrocarbon radical, with formaldehyde and thereby producing acondensattion product.

7. A process of reacting an alpha-alkyl substituted acrylic acid amidewith formaldehyde and thereby producing a condensation product.

8. Aprocess of reacting polymeric alpha-alkyl substituted acrylic acidamide with formaldehyde and thereby producing a condensation product.

9. A process of reacting methacrylamid'e and formaldehyde and therebyproducing a condensation product.

10. A process of reacting polymeric methacrylamide and formaldehyde andthereby producing a condensation product.

11. A process of reacting an amide of acids of the acrylic acid serieshaving the general formula wherein R is a radical of the groupconsisting of hydrogen and a hydrocarbon radical, with a lower molecularweight aliphatic aldehyde in the presence of a hydroxyl-containingcompound and thereby producing a condensation product.

12. Aprocess of reacting an amide of acids of the acrylic acid serieshaving the general formula wherein R is a radical of the groupconsisting of hydrogen and a hydrocarbon radical, with a lower molecularweight aliphatic aldehyde in the presence of a lower aliphatic alcoholand thereby producing a condensation product.

13. A process of reacting the monomeric amides of acids of the acrylicacid series having the general formula 1 wherein R is a radical of thegroup consisting of hydrogen and a hydrocarbon radical, with lowermolecular weight aliphatic aldehydes and subsequently polymerizing theresulting product.

sation product while in the presence of lactic acids. 1

17. A process of reacting para-iormaldehyde with monomericmethacrylainide in the presence of normal hutanol, sodiu hydroxidewherein R is a radical oi the group consisting of hydrogen and ahydrocarbon radical, and a lower molecular weight aliphatic aldehyde.

19; A polymer of the monomeric composition of claim 18.

20. A monomeric condeilflntion product o1 an amide of an acid oi theacrylic acid pri 'the general formula wherein R. is a radical of thegroup consisting of aldehyde. v v

" 24. A monomeric condensation product of methacrylamide. a lowermolecular weight ali- 'phatic aldehyde, and a lower molecular weightaliphatic alcohol.

25. The polymer of the monomeric composition of claim 24.

36. A monomeric condensation product of methaorylaniide, iormal fihydeand normal buanp 27. A polymer of the monomeric composition claim 26. v

28. The process which comprises condensing polymeric methacrylic amidewith formaldehyde.

29'. The process which comprises condensing methacrylic amide withformaldehyde.

30. The process which comprises condensin methacrylic amide withformaldehyde and polymerizing the resulting product.

DANIEL E. S'I'RAIN.

